1. Field of the Invention
The present invention relates to a key cylinder that operates an engaging member when a key is inserted into a rotor and rotated.
2. Description of the Related Art
Key cylinders having a main rotor accommodated in a cylindrical holder, and a rear rotor are known in the art. In one such key cylinder, the rear rotor is assembled to the main rotor by a pull-out preventing component of a ring cap that is engaged with the cylindrical holder. The main holder, rear rotor and ring cap are assembled to the cylindrical holder. Movement of the main rotor forward (in the key extraction direction) is stopped by a guard portion of the cylindrical holder. Movement of the main holder rearward (in the key insertion direction) is stopped by the ring cap through the rear rotor (see Japanese Patent Application Laid-Open (JP-A) No. 7-150830).
In such a key cylinder, when a key (authentic key) is inserted into the main rotor, left and right levers provided on the main rotor are able to latch to the rear rotor. Therefore, when the key is rotationally operated, the main rotor is rotated, and the rear rotor is rotated.
When an insertion member that is not the authentic key (an incorrect key etc.) is inserted into the main rotor, the left and right levers provided on the main rotor are not able to latch to the rear rotor. Due to this, even if the insertion member is rotationally operated, even though the main rotor is rotated, the rear rotor is not rotated.
However, in such a key cylinder, there are separate parts for the ring cap having the function of being able to stop movement of the main rotor in the forward direction and in the rearward direction, and for the left and right levers having the function of being able to make the rear rotor rotatable with the rotation of the main rotor.